The invention relates to copying and duplicating work.
More particularly, the invention relates to the use of electrostatic or xerographic copying or duplicating machines, especially of the type in which the originals to be copied are laid face down upon a transparent support plate to be illuminated by copying light.
I have already considered the possibility of providing copying machines with masks defining line-unblocking slits and shifting a multi-line original laid on top the masks linewise, to unblock successive lines of the original for successive copying operations. The slit-defining masks may be plain white cover-over masks or may be provided with inscriptions or the like. With the possibilities already considered by me, the arrangement which effects the line-by-line advancement of the multi-line original relative to the line-unblocking slit includes holding means. These holding means are located along those edges of the transparent support plate which run transverse to the line direction, i.e., parallel to the direction in which the step-by-step advancement mechanism shifts the multi-line original from one copying operation to the next.
Depending upon the variety of factors, including the design of the copying machine which is to be provided with the step-by-step advancement mechanism accessory for shifting multi-line originals, and also including other spatial considerations such as the size and shape of the multi-line originals to be handled, such a disposition for the holding means for the multi-line originals and the various masks may be unsuitable. This is irrespective of whether the step-by-step advancement mechanism for shifting multi-line originals and/or the mechanism for interchanging masks from an inseparable part of the copying machine or are removably mounted accessories, for example of the type purchased by a customer months after the purchase of the copying machine proper, when his particular copying needs have become clearer to him.